HR: 0830h
AN: H51C-1065    [PDF]
TI: Modeling phosphorus transport in surface flow under non-equilibrium conditions
AU: * Kim, K
EM: kkim13@uiuc.edu
AF: Agricultural and Biological Engineering Department, University of Illinois, Urbana-Champaign, 1304 W. Pennsylvania Avenue, Urbana, IL 61801 United States
AU: Kalita, P K
EM: pkalita@uiuc.edu
AF: Agricultural and Biological Engineering Department, University of Illinois, Urbana-Champaign, 1304 W. Pennsylvania Avenue, Urbana, IL 61801 United States
AB: Phase of chemicals - gaseous, dissolved or immobilized - may affect its transport in surface flow. Highly soluble chemicals are primarily transported in dissolved form while relatively less soluble chemicals are transported as being attached to sediment. Therefore, in modeling the movement in surface flow of the less soluble chemicals, it is important to consider sediment dynamics. Also adsorption kinetics between the less soluble chemicals and sediment should be considered in cases where dissolved chemicals are a major concern even though their concentration in the flow is relatively low. Chemicals such as phosphorus and ammonium reportedly take days to reach an equilibrium state, while some heavy metals and pesticides take minutes or hours. Thus, most chemical transport models, which have been developed based on equilibrium state assumption, may not be appropriate for predicting less soluble chemicals. In this study, dynamical modeling is attempted for phosphorus and sediment transport in overland flow and channel flow considering the interactions of phosphorus with suspended sediment and land surface or channel bed. Two models are developed in slightly different forms for the transport in each of overland flow and channel flow. The models consist of the kinematic wave equation for flow rate and the continuity equations for sediment, dissolved phosphorus and adsorbed phosphorus, and equations for land surface or channel bed. The effects of sediment dispersion as well as dissolved phosphorus dispersion are included for channel flow while they are ignored for overland flow. The model is applied to data from field experiments where sediment concentration, dissolved phosphorus concentration, and adsorbed phosphorus amount were measured at the outlet of the channel in small time intervals.
DE: 1815 Erosion and sedimentation
DE: 1860 Runoff and streamflow
DE: 1871 Surface water quality
SC: Hydrology [H]
MN: 2003 Fall Meeting